Sarah+Thompson

New Methods to Stop Counterfeiting Wiki post #7 

Counterfeit prodmedia type="youtube" key="YaX69OPEN6Q" height="364" width="450" align="left"ucts create losses in the billions each year. Beside the economic damages, quite often additional risks arise from the poor materials and bad workmanship of "knock-off artists." Recently chemists have realised that with the aid of fluorescing dyes, materials can be individually tagged and identified with certainty.

For quite some time now, product piracy has been affecting more than just watches and designer clothing. Specialized security features, like watermarks, bar codes, RFID tags and holograms label the products, and safeguard them from falsification, theft and manipulation. So when it comes to security features: the more complicated it is to imitate a brand, the more secure the system.

Fluorescence can be found in some organic dyes: Irradiate them within a certain wave length range, and they emit their own light with a greater wavelength. The type of luminosity—i.e., wavelength and light intensity—depends on the physical and chemical properties of the materials to which the dye was applied. Many dyes react to different properties, such as pH value or viscosity.

To make a product counterfeit-proof, the researchers add several dyes to the material. Thanks to the slight dosing, it is virtually impossible to decode the type and quantity of the dye additives: just a few parts per billion of dye concentrates is enough to mark the material. Another advantage: The counterfeit protection definitely cannot be removed. "Using conventional security features, the spot with the labelling can be eliminated from the material, theoretically speaking. But that approach doesn't work with our technology, since the dye permeates the entire material, and itself is a component of the identification label," says Holländer. This process is also helpful for an effective quality assurance, such as with coatings. With the aid of various dyes, manufacturers can monitor the chemical composition, degree of dryness and the thickness of the coat during the production process.

Reference:

Fraunhofer-Gesellschaft (2010, June 15). Brilliant counterfeit protection. //ScienceDaily //. Retrieved June 16, 2010, from http://www.sciencedaily.com­ /releases/2010/06/100614093627.htm Gold nanoparticles Create Visible-light Catalysis in Nanowires Wikipost #6

media type="youtube" key="uyhxRIvw_cY" height="364" width="594" align="center"  This video does not pertain to this post in the sense that it is not about but I feel it does explain how the gold nanoparticles work.  A scientist at the U.S. Department of Energy has created visible-light catalysis, using silver chloride nanowires decorated with gold nanoparticles that may decompose organic molecules in polluted water.  Traditional silver chloride photocatalytic properties are restricted to ultraviolet and blue light wavelengths, but with the addition of gold nanoparticles, they become photocatalytic in visible light. The visible light excites the electrons in the gold nanoparticles and initiates reactions that culminate in charge separation on the silver chloride nanowires. Tests have already shown that gold-decorated nanowires can decompose organic molecules such as methylene blue.  Reference: DOE/Argonne National Laboratory (2010, June 15). Gold nanoparticles create visible-light catalysis in nanowires. //ScienceDaily//. Retrieved June 16, 2010, from http://www.sciencedaily.com­ /releases/2010/06/100615122534.ht

PEI’s Red Soil Wiki post #5

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People from all over the world travel to Prince Edward Island to see all it has to offer. Many are amazed when they arrive and see that the dirt on the side of the road is not brown as it usually is, but a dark red, rusty colour. The red soil takes its colour from the high iron oxide content, which rusts when it is exposed to air. Prince Edward Island’s famous red sand can be seen everywhere, from the side of the road to its beautiful beaches that are framed by red sandstone cliffs. Iron oxide is commonly known as rust. ­For iron to become iron oxide, three things are required: iron, water and oxygen. This is what happens when the three come in contact with each other:

When a drop of water hits an iron object, two things begin to happen almost immediately. First, the water, which is a good electrolyte, combines with the carbon dioxide in the air to form a weak carbonic acid, which is an even better electrolyte. As the acid is formed and the iron is dissolved, some of the water will begin to break down into its component pieces—hydrogen and oxygen. The free oxygen and dissolved iron bond into iron oxide, in the process freeing electrons. The electrons liberated from the anode portion of the iron flow to the cathode, which may be a piece of a metal less electrically reactive than iron, or another point on the piece of iron itself.

The chemical compounds found in various aqueous solutions such as acid rain, seawater and salt-loaded sprays from snow-belt roads make them better electrolytes than pure water, allowing their presence to speed the process of rusting on iron and other forms of corrosion on other metals. Because the soil on the island is rich with sea water, it speeds up the process of rusting. References: <span style="color: #c00000; font-family: Arial,Helvetica,sans-serif; font-size: 12pt;">Eco-Sites of Canada. (2008, March 3). //Prince Edward Island//. Retrieved from http://www.ecokids.ca/pub/eco_info/topics/landuse/ecosites/pei

<span style="background-color: #000000; color: #ffffff; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 150%; text-align: center;">Make-up throughout the Ages Wiki post #4



Ancient Egyptian royalty has been known for their elaborate eye make-up. Queen’s such as Nefertiti and other ancient Egyptians believed that this make-up contained healing powers along with the protection of the Gods Horus and Ra as well as warding off illness. <span style="font-family: 'Lucida Sans Unicode','sans-serif'; font-size: 12pt; line-height: 115%;"> Clearly magic is not a scientific explanation. The lead-based makeup used by the Egyptians had antibacterial properties that helped prevent infections common at the time. A French chemist sates, “It was puzzling; they were able to build a strong, rich society, so they were not completely crazy. But they believed this makeup was healing—they said incantations as they mixed it, things that today we call garbage.”

The same French chemist, Dr. Christian Amatore and his fellow researchers used electron microscopy and x-ray diffraction to analyze several dozen sample from Egyptian makeup preserved at the Louvre. They found that the makeup was composed primarily of four lead-based chemicals: galena (which produced dark tones as well as gloss), the white materials cerussite, laurionite, and phosgenite.

Because the sample had disintegrated over the centuries, the researchers were not able to determine what percentage of the makeup was lead. Although many written texts, paintings and statues from this time period indicate that the makeup was extensively used, Egyptians saw it as magical not medical.

They thought it to be magical when the Nile flooded and they received infections caused by particles that entered the eye and caused diseases and inflammations. The lead-based makeup acted as a toxin, killing the bacteria before it got the chance to spread. Though these studies shine an interesting light on ancient culture, most scientists say that this makeup is not something that should be used in the present day.

Scientists believe this because they think that the toxicity of lead compounds overshadowed the benefits and that there were too many documented cases of poisoning as a result of lead in pains and plumbing in the 20th century. Even so, they still concur that the Egyptians being attracted to the compounds was logical at the time as lead and arsenic make beautiful colour pigments.

While some advocacy groups and doctors argue that, over time, lipstick wearers might absorb levels of lead that could lead to abnormal behaviours; the //Food and Drug Administration// has said that trace amounts of lead in makeup are too small to cause harm.

“It’s the dose that makes the poison,” says accomplished chemist Dr. Langerman. “A low dose kills the bacteria. In a high dose, you’re taking in too much.”

References: Bhanoo, S.N. (2010, January 18). Ancient egypt’s toxic makeup fought infection, researchers say. //The New York Times//,

<span style="background-color: #002060; color: #ffffff; display: block; font-family: 'Comic Sans MS',cursive; font-size: 160%; text-align: center;"> Wikipost #3** <span style="color: #002060; display: block; font-family: 'Comic Sans MS'; font-size: 18pt; line-height: 115%; text-align: center;"> The microwave is one of the many great inventions of the 20th century. Microwaves can be found in millions of homes and businesses around the globe. At one time or another, we’ve all been told not to put aluminum foil in the microwave. The explanation for this is that it will start a fire or even an explosion. The question is, why can’t you put aluminum in the microwave?
 * Why Can't we put Aluminium in the Microwave?

Though microwaves seem complex, the technology behind them is actually quite simple. They use microwaves to heat food. In the case of microwave ovens, the commonly used radio frequency is roughly 2.5 gigahertz. Radio waves in this frequency have some interesting properties: water, fats, and sugars absorb them. After they are absorbed they are converted directly into atomic motion—heat. Another interesting property: most plastics, ceramics or glass do not absorb the waves. <span style="color: #333333; display: block; font-family: 'Arial','sans-serif'; font-size: 9pt; line-height: 115%; text-align: center;"> The inside walls of a microwave are actually made up of metal. A fairly thick piece of metal works a lot like a mirror but instead or reflecting an image, it reflects microwaves. This is why if you put food in a metal pan in a microwave, the food will not cook as the metal pan would absorb all of the microwaves. However, thin, tiny and/or sharp pieces of metal do not.

Because the walls of the microwaves are substantial pieces of metal, they can usually tolerate these currents without any problems. But, the thin or tiny pieces of metal such as aluminum foil are overwhelmed by those currents and heat up so quickly that they can cause a fire. Also, if the foil is crumpled up so that there are sharp edges, the electrical current will cause sparks. When and if these sparks hit something else in the microwave such as a plastic spoon or plastic wrap this will most likely cause a large enough fire for you to need a fire extinguisher.

Though it is very unlikely that a small piece of foil is going to cause your microwave to explode, it will do a significant amount of damage. So, the next time you use a microwave; don’t forget to use paper towel, plastic wrap or any other non-metal kitchen aids. Also, remember that aluminum is not the only dangerous metal in a microwave. You should avoid putting any metals in the microwave.

References: Marshall, B. (2008, March 24). //What if I put aluminum foil in the microwave?//. Retrieved from http://science.howstuffworks.com/aluminum-foil-in-the-microwave.htm#

<span style="background-color: #00b050; color: #ffffff; display: block; font-family: Bookman Old Style; font-size: 14pt; line-height: 115%; text-align: center;">A New Form of Cooking Wikipost #2


 * [[image:Soybeans.jpg width="228" height="181" align="center"]] || [[image:Cooking-Oil.jpg width="210" height="183" align="center"]] || [[image:Soybeans.jpg width="227" height="180" align="center"]] ||

<span style="color: #00b050; font-family: 'Bookman Old Style','serif'; font-size: 14pt; line-height: 115%;">Philip Jessop, the Canadian Research Chair in Green Chemistry, has created a solvent that may revolutionize cooking oil production. When this solvent is combined with carbon dioxide, it extracts oil from soybeans. Currently, cooking oils are made using hexane, which is a cheap, flammable solvent that is a neurotoxin and creates smog. This process uses large amounts of energy as it involves distillation. Jessop says, “Carbon dioxide is famous for global warming—it’s everybody’s favourite gas to hate these days. My research group is trying to figure out if we can use it for something useful. I figure we may not be able to recycle all the carbon dioxide out there but we can recycle a bit of it and make it contribute to society in a positive way.”

The new method developed by Jessop and his team of making oil involves a “switchable” solvent. The solvent is hydrophobic, meaning it does not mix with water but does mix with oil. However, when carbon dioxide is added, the solvent becomes hydrophilic, meaning it likes to be in water but doesn’t like to be in oil. So, when carbon dioxide and water (carbonated water) is added to a mixture of this new solvent and soybeans, it extracts oil out of the soybeans and the oil is collected. When the carbon dioxide is removed, the solvent switches back to its hydrophobic state. Everything is recycled as the water and solvent can be used again.

Several cooking oil companies have shown interest in Jessop’s studies though it is still years away before it can be used in a large-scale oil manufacturing. To get their product ready, Jessop and his team still have to do economic calculations to see if this new solvent will survive in the industry. References: <span style="color: #00b050; font-family: 'Bookman Old Style','serif'; font-size: 14pt; line-height: 115%;"> Queen's University (2010, March 30). Chemistry discovery may revolutionize cooking oil production. //<span style="font-family: 'Bookman Old Style','serif';">ScienceDaily //. Retrieved April 8, 2010, from http://www.sciencedaily.com­ /releases/2010/03/100329123317.htm

<span style="background-color: #404040; color: #ffffff; display: block; font-family: Arial Black; font-size: 16pt; line-height: 115%; text-align: center;">Why does hair turn grey??? Wikipost #1

Have your parents ever told you that you are going to make their hair turn grey? Well, that is not exactly the truth. Too much stress can cause a loss of hair. The loss of pigmented hair can make those extra grey hairs more noticeable. The greying of hair is one of the many examples of chemistry at work in your own body! To understand this process a little more clearly, first let’s take a closer look at hair.

You have over 100 000 strands of hair on your head. It sounds like a lot, but hair actually has the highest rate of cell division in your body and is the second fastest growing tissue, the first being bone marrow. This is the reason why you will notice that your hair grows about 1 centimetre every month.

Each hair on your head is surrounded by a tissue underneath the skin called a follicle. From each follicle grows little cells called keratinocytes which build up the keratin that is our hair (our skin and fingernails are also composed of keratin). Every follicle contains certain pigment cells called melanocytes which are constantly producing a chemical called melanin. This is the chemical responsible for your hair colour whether it is red, brown, black or blonde. What colour your hair is depends on your genes as does the rate at which your hair turns grey.

Now we know what our hair is and why it is coloured the way it is, but why does it turn grey when we get older? As we age, the pigment cells in our hair follicles gradually die off. As the pigment cells die off, they will stop producing melanin. The strand of hair will lose its colour leaving the hair more of a transparent colour such as grey or white. The age at which your hair turns grey depends on your genetics. An easy way to get a rough estimate of when your hair will start to grey is by asking your family members when their hair began to grey and base your guess off of their answers. Don’t worry if you start to notice a few grey hairs now, it can take ten years or more for your all of your hair to go grey!

Even though genetics are the most common cause of grey hair other deficiencies can contribute to the greying process as well. Things such as a lack of B vitamins, specifically pantothenic acid, poor nutrition, anaemia (lack of iron in the blood), thyroid problems, and smoking can cause your hair to grey. Smoking leads to premature hair greying as smoking depletes oxygen in our body tissues. Also, treatments for diseases like AIDS or cancer can cause your hair to grey.

Unfortunately, once your hair goes grey there is no way to turn it back. The only way for your hair to return to its previous or original state is to dye it. The following video gives some tips and tricks on covering grey hair.

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References: Scolari., S. (2010, March 03). //Why does Hair turn gray as we age?//. Retrieved from <span style="color: #4d4d4d; font-family: 'Arial','sans-serif'; font-size: 12pt; line-height: 115%;">[] Edmonds., M. (2009, July 29). //Does Stress really make your hair go gray faster?//. Retrieved from <span style="font-family: 'Arial','sans-serif'; font-size: 12pt; line-height: 115%;">[|http://health.howstuffworks.com/human-nature/health-myths/stress-gray-hair1.htm#]